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Sep 24th 2011 | from the print edition
A More Perfect Heaven: How Copernicus Revolutionised the Cosmos. By Dava Sobel. Walker & Company; 272 pages; $25. Bloomsbury; £14.99 . Buy from Amazon.com, Amazon.co.uk
THE common rule in biography is that the more important the subject, the heavier the tome—with both pages and piety. Dava Sobel flouts this convention. Famous for her delightfully quirky books on the history of science, starting with the 1995 bestseller, “Longitude”, she delivers here a refreshingly fast-paced and breezy account of the life of Nicolaus Copernicus, the Polish cleric who knocked the Earth from its perch at the centre of the solar system and put the sun in its place.
Ever since Claudius Ptolemy published the “Almagest” in the second century AD, almost all astronomers had believed that the Earth lay at the centre of the universe. The sun, the planets and the stars supposedly revolved around it once a day. It was a faith reinforced by common sense, a reverence for the wisdom of antiquity, and its resonance with Christian mythology. Geocentrism fit with several passages in the Bible, and with the church’s view of the world more generally, which held that the Earth, as the abode of God’s greatest creation, sat at the centre of everything. Ptolemy’s model was complex, with planetary orbits modified by smaller orbits (called epicycles), but it fit with observations, and could even be used to predict what the night sky would look like at an arbitrary date in the future.
It is not known when the idea of a sun-centred cosmology came to Copernicus. He was not the first to dream it up: Aristarchus of Samos, a Greek astronomer, proposed something similar around 250BC, although no details of his system survive. Copernicus’s first speculations on the subject appear in a 40-page booklet printed before 1514, which he circulated to some friends and colleagues. Although he continued to refine the theory, he was reluctant to publish, either because he feared ridicule for such an outlandish suggestion, or because he worried about a reaction from the church. Indeed the church would imprison Galileo Galilei, an Italian astronomer, for advocating the sun-centred model of the universe a century later.
But Copernicus did eventually publish his celestial theory at the end of his life. One person seems to have been instrumental in persuading him to go ahead, a scholar called Rheticus, or Georg Joachim von Lauchen, a young mathematician who arrived on Copernicus’s doorstep in 1539 and spent two years as his pupil.
In her introduction, Ms Sobel writes that she has long been fascinated by this meeting. She uses the book to imagine what took place between the two men, presenting it in the form of a play. The scarcity of surviving evidence gives Ms Sobel some poetic latitude. Readers are treated to a demonstration of an arcane machine, subplots involving pederasty and concubinage, and a conspiracy to hide Rheticus’s presence (he was a Lutheran) from the Catholic bishop of Varmia. Rheticus ultimately overcomes his own doubts about Copernicus’s theory and manages to persuade his host to commit his ideas to paper.
“A More Perfect Heaven” does a good job of giving the flavour of life in Reformation-era Europe, at least among its intellectual elite. But there is strangely little discussion of the intellectual underpinnings of Copernicus’s system of the world, and of the meticulous observations that eventually convinced him that Ptolemy was wrong. It was a giant leap suddenly to argue that the Earth orbits the sun, rather than the other way around, particularly without telescopes. Imagine trying to deduce this with the naked eye, a sextant and little else. Then imagine the difficulties of defending it against the obvious criticisms in an era before mathematically rigorous physics: why are we not flung from the Earth if it spins round so fast? Why are there not hurricane-force winds? That Ms Sobel overlooks these questions is a shame, since it rather undervalues an immense intellectual achievement and leaves a noticeable hole in an otherwise excellent book.
Physicists have a stock phrase they trot out whenever someone claims to have made an astounding new discovery about the universe. "Important," they say, "if true."
It's a tactful way of saying "Don't bet on it," and they've been saying it a lot over the past day or so. The reason: a team of European scientists has reportedly clocked a flock of subatomic particles called neutrinos moving at just a shade over the speed of light. According to Albert Einstein's special theory of relativity, that can't be, since light, which cruises along at about 186,000 miles per second (299,000 km/sec.), is the only thing that can go that fast.
If the Europeans are right, Einstein was not just wrong but almost clueless. The implications could be huge. Particles that move faster than light are essentially moving backwards in time, which could make the phrase cause and effect obsolete.
"Think of it as being shot before the trigger is pulled," wrote University of Rochester astrophysicist Adam Frank on his NPR blog. Or, as Czech physicist Lubos Motl put it on his blog, "You could kill your grandfather before he had his first sex with your grandmother, thus rendering your own existence needed for the homicide inconsistent with the result of the homicide."
The evidence for this complete upending of modern physics and cosmic decorum comes from an experiment involving two top-notch physics installations. The first is CERN, the European Center for Particle Physics, near Geneva, where a particle accelerator created the swarm of neutrinos in the first place. These bits of matter are bizarre no matter how you look at them: they're so elusive that one of them could pass through a chunk of lead a trillion miles thick without a bump.
It's no surprise, then, that the swarm created at CERN could fly out of the accelerator, zip right through the Alps and appear in the Gran Sasso Observatory, located in a tunnel deep beneath Italy's Apennine Mountains. Most of the neutrinos kept on going, but just a few, by pure chance, were intercepted by one of the observatory's neutrino detectors. And when the two labs synchronized their watches, it appeared that the particles had made the 450-mi. (724 km) journey 0.0025% faster than a beam of light would have (if light could travel through mountains, that is).
That splinter of a second isn't much, but it's enough to overturn a century of firmly established physics, rewrite the textbooks and throw the faculties at major universities around the world into a collective tizzy. In short, it's really important.
If true.
No one is tearing up the Einsteinian rule book just yet. As physicists well know, astonishing results like this often turn out to be wrong, especially when they haven't been double-checked. Sometimes that means the group announcing the big news has done shoddy work, like the Utah chemists who announced to great fanfare back in 1989 that they'd achieved controlled nuclear fusion on a tabletop — the cold-fusion kerfuffle — trumping the physicists who'd been struggling for years to do the same thing with billion-dollar machines. Sometimes it just means the researchers have overinterpreted what they're seeing, as when NASA scientists said they'd found evidence of life in a rock from Mars.
And sometimes, the researchers have gone about things the right way, carefully checking their equipment and their calculations to make sure they aren't being fooled by some mundane, potentially embarrassing glitch. The Grand Sasso scientists have done just that kind of due diligence here, and you know what? They still can't find any evidence that they've missed anything.
But that doesn't mean they haven't. It's always possible that their instruments are misbehaving in too subtle a way for anyone to detect at this point. Given the stakes if the equipment is right — if neutrinos really can move faster than light — nobody's buying the shocking result until another set of researchers, using another set of instruments, gets the same answer. Indeed, that's exactly what Antonio Ereditato, of the University of Bern, leader of the Gran Sasso end of the experiment, is hoping for. He told the BBC: "My dream would be that another, independent experiment finds the same thing. Then I would be relieved." This very willingness to be double-checked — and proved wrong — gives the scientists greater credibility, even if the jury is still out on their findings.
A second opinion may be coming soon. A group at the Fermilab accelerator complex, near Chicago, says it's preparing to do just the follow-up round of studies Ereditato welcomes. As it happens, Fermilab physicists made their own faster-than-light neutrinos claim back in 2007. It too would have been important if true, but on closer analysis, the evidence went away. The Fermilab scientists immediately accepted the verdict that time, just as the Europeans undoubtedly will if this new "discovery" goes up in smoke, as physicists everywhere are betting it will.
Or maybe it won't: the history of science may be littered with claims that were ultimately proved false, but some outrageous ideas turn out to be true in the end. Take dark matter, the mysterious, invisible stuff that outweighs the visible stars and galaxies by a factor of 10 to 1. When it was first proposed in the 1930s, nobody believed it. When it reappeared in the 1960s, everyone laughed. Now it's firmly accepted as a fundamental part of the universe.
That kind of thing just might happen again. "Based on past experience, these results are probably wrong," writes Adam Frank at NPR.org, "but it sure would be a wild ride if they prove correct."
Sony is introducing binoculars that also record 3-D video.
Line2 HD puts phone calls, texts and voice mail and email on a single screen, and offers a stack of other features as well.
Bose's new SoundLink is a wireless speaker that connects through Bluetooth to your smartphone.
Americans pride themselves on being global leaders in innovation. So why is the nation lagging behind China and Germany on renewable energy?
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JX日鉱日石エネルギーは、ガスを使って発電と給湯をする家庭用燃料電池「エネファーム」の新型を10月17日に発売する。旧型より発電効率を1割向上 させ、「家庭の電気の7割をまかなえる」としている。また、停電時にも使用できるよう蓄電池とのセット販売も来夏に始める。
新型は、部品点数を減らした結果、旧型に比べて容積で40%小型化。価格は270万円(税込み、工事費別)で、旧型と合わせた販売目標は、今年度で1500台、来年度は4千台。
来夏には、リチウムイオン電池とつなぎ、停電時にもエネファームの運転を継続できるセット販売も始める。太陽光発電パネルを組み合わせた3点セットでの販売もする。ただ、価格はリチウムイオン電池だけでも約100万円と割高だ。
エネファームは東日本大震災後の節電意識の高まりで販売が好調。1台あたり105万円の国の購入補助金は、7月で年間8千台分の今年度予算が切れた。経済産業省は第3次補正予算での追加計上を要求する。
宇宙航空研究開発機構(JAXA)は9日、2015年以降に金星軌道への再投入を目指している探査機「あ……… (22:32)[記事全文]
慶応大の研究チームがiPS細胞(人工多能性幹細胞)技術を使い、アルツハイマー病が発症する仕組みの確……… (16:32)[記事全文]
過去にB型肝炎ウイルスに感染した人ががんやリウマチなどの治療で免疫力が落ちると、ウイルスが再び増え……… (01:01)[記事全文]
東レは9日、炭素繊維を車体に使った電気自動車(EV)の試作車を発表した。F1カーの元設計者を起用し、3億円の製作費をかけた。鉄より軽くて強いとされる炭素繊維を自動車業界で普及させるためのシンボルにする。
炭素繊維を骨格や座席、外板などに使い、車体の重さを従来のEVに比べ3分の2程度に抑えた。2人乗りのオープンカーで、最高速度が時速147キロ、充電1回で185キロ走る。F1カーのデザイナーだった英国人ゴードン・マレー氏に設計や製作を頼んだ。
東レは2015年以降、炭素繊維の自動車業界への本格供給をめざす。価格の高さが難点とされるが、鉄なら複数にわたる部品を、炭素繊維は一体で成型でき るため、車全体の製造費は抑えられるとみる。記者会見で田中千秋副社長は「高級車でなく普通車への供給をめざす」と語った。
Sep 3rd 2011 | from the print edition
A GOOD way to make yourself unpopular at dinner parties is to point out that a typical person is, from a microbiologist’s perspective, a walking, talking Petri dish. An extraordinary profusion of microscopic critters inhabit every crack and crevice of the typical human, so many that they probably outnumber the cells of the body upon and within which they dwell.
Happily, these microbes are mostly harmless. Some of them, particularly those that live in the gut, are positively beneficial, helping with digestion and keeping the intestines in good working order. That is no surprise—bacteria as much as people have an interest in keeping their homes in sound condition. What is surprising is the small but growing body of evidence which suggests that bacteria dwelling in the gut can affect the brain, too, and thereby influence an individual’s mood and behaviour. The most recent paper on the topic, published this week in the Proceedings of the National Academy of Sciences, reports (like much of the research in this field) on results in mice.
The researchers, led by Javier Bravo of University College, Cork, split their rodent subjects into two groups. One lot were fed a special broth containing Lactobacillus rhamnosus, a gut-dwelling bacterium often found in yogurt and other dairy products. The others were fed an ordinary diet, not fortified with microbes.
The team then subjected the mice to a battery of tests that are used routinely to measure the emotional states of rodents. Most (though not all) of these tests showed significant differences between the two groups of animals.
One test featured a maze that had both enclosed and open tunnels. The researchers found that the bacterially boosted mice ventured out into the open twice as often as the control mice, which they interpreted to mean that these rodents were more confident and less anxious than those not fed Lactobacillus.
In another test the animals were made to swim in a container from which they could not escape. Bacteria-fed mice attempted to swim for longer than the others before they gave up and had to be rescued. Such persistence is usually interpreted by students of rodent behaviour as evidence of a more positive mood.
Direct measurements of the animals’ brains supported the behavioural results. Levels of corticosterone, a stress hormone, were markedly lower in the bacteria-fed mice than they were in the control group when both groups were exposed to stressful situations. The number of receptors for gamma-aminobutyric acid, a natural chemical messenger that helps dampen the activity of certain nerve cells, varied in statistically significant ways between the brains of the two groups, with more in some parts of the treated animals’ brains and fewer in others. Most intriguing of all, when Dr Bravo cut the animals’ vagus nerves—which transmit signals between the gut and the brain—the differences between the groups vanished.
The idea that gut-dwelling microbes can affect an animal’s state of mind may strike some people as outlandish, and there are certainly loose ends still to be tied up. Beyond their evidence that the vagus nerve is crucial to the relationship, for example, Dr Bravo and his colleagues do not yet know the precise mechanisms at work. There is also an obvious follow-up question: whether a similar thing is going on in people. A few previous studies have hinted at the possibility. For example, bacterial treatments may help with the mental symptoms of illnesses such as irritable-bowel syndrome.
All this is forcing a reassessment of people’s relationship with the bacteria that live on and in them, which have long been regarded mainly as a potential source of infections. An editorial in this week’s Nature raises the possibility that the widespread prescription of antibiotics—which kill useful bacteria as effectively as hostile ones—might be one factor behind rising rates of asthma, diabetes and irritable-bowel syndrome. If Dr Bravo’s results apply to people, too, then mood disorders may end up being added to this list.
BY TETSUO KOGURE STAFF WRITER
2011/09/06
The government is set to draw up proposals for international standards evaluating product performance in a bid to help Japanese businesses fare better against price-competitive goods from China and other rivals.
The Ministry of Economy, Trade and Industry is expected to craft its proposals over the next couple of years for submission to international standardization organizations.
The proposals will cover 29 industries where Japan is strong, such as light-emitting diode bulbs, antibacterial textiles and household fuel cells.
Japan has fallen behind the United States and EU countries in the quest for international standardization.
Japan-initiated standards were mainly for products that have smaller markets.
Japanese manufacturers have been put at a disadvantage in the world market because Chinese companies grabbed market share by quickly releasing products similar to theirs, but at much lower prices.
There have been growing calls inside Japan to create a framework that highlights differences in the quality of Japanese and Chinese products.
"Increasingly, it has become important for Japan to get involved in making rules assessing product performance," a ministry official said.
As for LED bulbs, an industry in which Japanese makers have begun mass production, the government is expected to propose to the Geneva-based International Organization for Standardization in fiscal 2012 a method to measure the brightness of a bulb per unit of electric power.
Japan is expected to work with the United States and France to put this plan in motion.
Japanese manufactures use a number of formulas to gauge the energy-saving qualities of their products.
This makes it harder to objectively assess the performance of LED bulbs, which are said to last four to seven times longer than fluorescent lights.
The global market for lighting is estimated at 10 trillion yen ($129.87 billion) a year.
Chinese companies are also rolling out LED bulbs.
The Japanese government fears that, without international performance standards, Chinese makers may market less expensive products, billing them as environmentally friendly based on their own performance tests.
With respect to household fuel cells, used to make electricity and hot water out of gas, the government will propose to the International Electrotechnical Commission, also in Geneva, next fiscal year a method to assess the safety and energy saving feature of the products.
The move is aimed at preparing for the entry of Chinese producers in the future.
Right now, only Japanese companies manufacture household fuel cell on a commercial basis.
The government will also propose to the ISO by the end of the current fiscal year a measure to gauge the performance of sweat absorbing, antibacterial and static protection features of high-function textile.
Other products the government is trying to protect include those involving solar cells or regenerative medical techniques as well as welfare equipment.
International standards at the ISO and IEC are adopted by a majority vote by its member countries.
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